A. More and more organizations are moving to an IP-based connectivity model for external storage, especially with the increase in iSCSI availability and Network File System (NFS) usage.
There's no definitive right answer to this question, but there are factors to consider. Virtualization loads typically consist of lots of small, block random I/O. For this type of load, IP and FC will probably be very similar in performance, with IP potentially having a slight speed advantage. For large block I/O, however, FC will outperform IP, because the block size of FC is much larger than IP.
Also consider that IP generally has less complex hardware requirements, with only network cards and switches required, while FC requires special interface cards and connectors.
The best answer is to try and use external storage that supports both IP and FC so you can choose based on your requirements.
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